It isn't quite racing's version of Brangelina but Weary-Dunlop might just be a partnership to watch.

Weary, of course, is the Chris Waller-trained import who looked to be a star on the rise with back-to-back Group One placings last autumn.

Dunlop is a pony who once went by another name, until he became Weary's constant companion.

The pair is almost inseparable, so much so that Dunlop is to Weary what the great Australian wartime figure `Weary' Dunlop was to so many - a great comfort.

"I would explain it as a friendship, him (Weary) having a companion. The pony gives him confidence," Waller said.

"He doesn't seem to stress and worry about his work on the way out to the track and therefore he just goes out and gets it done and comes back.

"It's pretty powerful when they're together, they get the job done."

A dual stakes placegetter in France, Weary made an immediate impact in Australia.

He won the Doncaster Prelude at his third Sydney start and was placed in the Doncaster Mile and All Aged Stakes.

Hopes for a lucrative spring were high but the horse under-delivered.

He finished unplaced in three runs and didn't make it to his initial goal of an Epsom Handicap start.

Enter Dunlop the pony.

"We had always been able to get away without a pony, then we got to the stage where we needed one," Waller said.

"Otherwise it was just a waste of a good horse."

Now Weary has a mate to hang out with, he is happy to perform his duties as a racehorse.

Waller said the horse's demeanour had changed since Dunlop came on the scene.

"He always looked well last preparation but didn't perform. Even on the track we were having a few troubles with him concentrating," Waller said.

"This preparation has been a breath of fresh air so far."

Weary is one of five Waller-trained runners in Saturday's Expressway Stakes at Rosehill and, as the $5 second favourite, the most fancied.

He traditionally performs first-up, handles rain-affected ground and has respectable form around the 1200m trip.

Saturday's renewal has also attracted classy mare Driefontein and promising three-year-old Panzer Division but Sydney's leading trainer says the absence of a superstar has made it winnable.

"If Black Caviar was in there or one of Joe Pride's good sprinters at the moment you'd say, `well we can't win the race'," Waller said.

"But it's not an overly strong race so it's going to give us a chance at least."